# File extension for CommonMark?

**URL:** <https://talk.commonmark.org/t/file-extension-for-commonmark/440>\
**Category:** Spec\
**Created:** [September 6, 2014, 2:38am UTC](https://talk.commonmark.org/t/file-extension-for-commonmark/440 "2014-09-06T02:38:59Z")\
**Posts on this page:** 1\
**Showing post:** 41

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**Author:** ![Sanpi](https://cdn.commonmark.org/user_avatar/talk.commonmark.org/sanpi/32/401_2.png) [@Sanpi](https://talk.commonmark.org/u/Sanpi)\
**Post date:** [September 18, 2014, 9:01am UTC](https://talk.commonmark.org/t/file-extension-for-commonmark/440/41 "2014-09-18T09:01:08Z")

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> [@rlidwka](#):
>
> CommonMark is Markdown

Not exactly: [Is CommonMark really Markdown "compatible"? - #2 by codinghorror](http://talk.commonmark.org/t/is-commonmark-really-markdown-compatible/540/2)

> [@rlidwka](#):
>
> (I mean, every cmark implementation works as a markdown parser, but the opposite isn’t true).

A new extension doesn’t means you can’t parse `.md` file as CommonMark, but prevent parsing CommonMark file with a markdown parser.

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_[View the full topic](https://talk.commonmark.org/t/file-extension-for-commonmark/440)._